The invention relates to a ventilating device for a motor vehicle, having an air filter, having a fan and having a plurality of ventilation openings which can be connected to the fan, are provided for the ventilation of the motor vehicle and are arranged in a central region and in a lateral region of an instrument panel (dashboard).
Such ventilating devices are often used in motor vehicles nowadays and are thus known. The ventilating device usually has a multiplicity of ventilation openings in the instrument panel, or in the vicinity thereof, and in a footwell of the motor vehicle. The ventilating device takes in fresh air through a fresh-air opening arranged on the outside of the motor vehicle and feeds it, by means of the fan, to the ventilation openings arranged in the motor vehicle. It is often possible to feed fresh air from the fresh-air opening into the motor vehicle by a changeover flap or to change the fan to a circulating-air feed, in the case of which the air is taken in in the footwell of the motor vehicle and fed, via the air filter, to the ventilation openings in the instrument panel. It is also known for at least individual ventilation openings, with the fan being bypassed, to be connected directly to a fresh-air opening arranged on the outside of the motor vehicle and for said ventilation openings to have fresh air admitted to them directly when the vehicle is moving forward.
The disadvantage with the known ventilating device is that it usually takes a very long time to exchange the stale air in the motor vehicle. In particular if an occupant is smoking in the front region of the vehicle, this means that the stale air is in the vicinity of the instrument panel, or above the latter, and, in the case of the known ventilating device, is mixed, by way of the air blown in through the ventilation openings of the instrument panel, with the rest of the air in the passenger compartment.
It would be possible to envisage providing separate ventilation openings, connected to a dedicated fan, in the motor vehicle. It would then be possible for the fan to extract the stale air from the passenger compartment of the motor vehicle through the separate ventilation openings. However, such a ventilating device is highly complex in structural terms and requires a large amount of space for the installation of ventilating ducts.